[llvm] [Xtensa] Implement THREADPTR and DFPAccel Xtensa Options. (PR #145543)

[Andrei Safronov via llvm-commits]

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@@ -207,6 +213,14 @@ MCRegister Xtensa::getUserRegister(unsigned Code, const MCRegisterInfo &MRI) {
     return Xtensa::FCR;
   } else if (MRI.getEncodingValue(Xtensa::FSR) == Code) {
     return Xtensa::FSR;
+  } else if (MRI.getEncodingValue(Xtensa::F64R_LO) == Code) {
+    return Xtensa::F64R_LO;
+  } else if (MRI.getEncodingValue(Xtensa::F64R_HI) == Code) {
+    return Xtensa::F64R_HI;
+  } else if (MRI.getEncodingValue(Xtensa::F64S) == Code) {
+    return Xtensa::F64S;
+  } else if (MRI.getEncodingValue(Xtensa::THREADPTR) == Code) {
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andreisfr wrote:

I rewrote the function code.

https://github.com/llvm/llvm-project/pull/145543